New shower enclosure leaks at wall / base

I recently replaced (with help) an old shower enclosure with fiberglass rear surround for a glass-wall surround with tile against the walls.

The Vigo unit was installed and caulked with silicone caulk per the instructions:

- Inside between the side walls and the side seal strip (where the glass walls meet the tile)
- Inside of the bottom of side glass panels where they meet the bottom metal rail
- Inside perimeter of metal rail where it meets the base and along the tile where it meets the base

The instructions call for silicone caulk along the inside where the glass wall joins the metal base, as well as along the side walls where the unit touches the tile, as well as along the bottom edges of the tile and the metal frame below the glass sidewalls.

The shower leaks in the corners where the sidewall meets the tile and base. I've rechecked the interior caulk, and it all looks solid, but I suppose I could be missing something.

I'm tempted to caulk on the outside too, where the leak is, but I'm concerned that'll just trap water and make a small problem larger down the road. I don't want to repaint the walls until I get the leak fixed.

If water gets into the bottom rail, that is where it will leak out, but you have to stop it from getting in, not just keep it there by sealing the outside.

Click to expand...

Yes, indeed. Now the trick is to run enough water down the glass wall to see if it is getting past the silicone sealer down into the rail, or if it is coming from somewhere else (perhaps through the grout as suggested above).

For my first experiment, I ran strips of 2" masking tape along the glass sidewalls, covering the point where the glass enters the bottom rail. After a shower, I did not have water leaking as shown in the previous post. This was a quick and dirty test, and the edges were certainly not sealed well at all, but still, no water leaked.

I guess I need to look closer, because there appears to be a very thin, clean line of silicon caulk where the glass meets the bottom rail.

I think I may need to get some close-ups, but here are some shots. I'm wondering if the water is coming in at the joints between the three bottom rail pieces as opposed to running down the glass and into the bottom rail.

So after 5 more showers, complete with fresh 2" masking tape across the bottom of the glass on the two sides of the shower, I've had no more leaks from the corners. Of course, this isn't an ideal long term solution.

So - should I just lay down another line of silicone caulk where the glass meets the bottom rail? Would I need to try to remove the existing caulk along that seam?

The masking tape has been working amazingly well, which pretty much confirms that the water is entering the rail by running down the glass. Even though it appears to be well caulked with silicone, when I cover up that area with the masking tape, I get no water leaking from the end of the bottom rail.

Any advice on the caulking? Do you need to try to cut out what is there? The caulking is now about 2 months old. Also - how long do I need to let it dry after the last shower before I try to caulk it?

Thanks for the info. The glass installer I spoke with suggested that if it was a clean caulk line that I should first clean it, and try to caulk over it with a larger bead seeing that the caulk was relatively clean. If that doesn't work, he suggests I may have to disassemble the side walls and clean the silicone caulk from the glass and the bottom rail and try again.

Just to follow-up. I let it dry for 40 hours with a fan running on it, cleaned out the existing (very small) bead of silicone caulk between the glass and the bottom rails. I re-caulked with a larger bead of caulk, making sure it sealed from edge to edge.